1. Field of the Invention
This invention relates generally to hydraulics and plumbing apparatus and in particular to such equipment designed for use with storage pool level control and drainage.
2. Description of the Prior Art
There is some interest in controlling the fluid level of pools and ponds and in particular swimming pools that are open. In the event of heavy rain a pool or exterior fish tank for example, could overflow and be damaged or cause damage to the surrounding area. Problems could be minimized if the caretakers of the pool were available to drain the pool or tank, however in the event of a major storm electrical power could be out and without pumps the caretakers would be helpless to act efficiently.
A number of U.S. Patents have been granted that are directed toward controlling the water level in swimming pools and the like. For example, U.S. Pat. No. 4,342,125 issued Aug. 3, 1982 to Hodge discloses an apparatus for maintaining the water level in a pool. U.S. Pat. No. 4,621,657 issued Nov. 11, 1986 to St. Ledger for an automatic water level monitoring system includes a manually adjustable overflow tube and a supply line operated by a diaphragm valve. The U.S. Patent granted to Lively for a swimming pool control system, U.S. Pat. No. 4,685,158 issued Aug. 11, 1987, is electrically controlled and would fail in the event of a power outage. The invention of Detloff, as disclosed in U.S. Pat. No. 4,735,230 and issued Apr. 5, 1988 for an overflow valve system for swimming pools amounts to a water-closet ballcock that will limit the inflow of water to a pool or tank. U.S. Pat. No. 5,253,374 issued Oct. 19, 1993 to Langill discloses a complicated system of plumbing to maintain water level in a pool with out the need for electrical assistance.
There is a need then for a simple, reliable and inexpensive means for overflow protection for open pools exposed to the elements of the weather.